At 200 feet per second. We need to take a minute and say [Elliot]’s gun is stupidly unsafe. He used PVC pipe to hold air pressure, so that may… explode one of these days. Also, the AA ...

You don’t need any of that chemical nonsense to just have fun, though, as this compressed air cannon from [OtisLiu153] demonstrates. The build uses PVC pipes for both the barrel and the air tank.